Managing Rats Naturally



This beautiful small hawk, a Black-shouldered Kite, is a regular visitor to the Narara Ecovillage. Either perched on the mulberry tree or an old power pole, or hovering like a small angel, it has been a pleasure to watch.

Two weeks ago I was lucky enough to see it drop to the ground, grab something and then fly up to a nearby greenhouse frame.  On inspection through binoculars, its prey was revealed to be a rat, almost as large as itself. On hearing of this, a loud cheer went up from a local (human) resident!

Coincidentally at almost exactly the same time Michael Lohr, a PhD student in Western Australia, published his research (1) showing that rat poisons, once ingested by rats, can go on killing anything that eats them for many months. Victims can include owls and diurnal birds of prey (like our kite), as well as to many other animals, including pets like cats and dogs. Particularly dangerous and long lasting are the so-called ‘second generation’ anticoagulant rat poisons. In comparison, ‘first generation’ poisons work more slowly and break down more quickly.

Poisons.

Generally, stores in Australia carry only a few 1st generation poisons, and they are vastly outnumbered by 2nd generation products. If you exhausted all other possibilities (see below), and feel you HAVE to use rat poisons,  choose “First generation” products that have warfarin or coumatetralyl as the active ingredients (e.g. ‘Ratsak Double Strength’ is a warfarin product and ‘Racumin’ is a coumatetralyl product).  Don’t use those with  brodifacoum, bromodialone or Difenacoum (e.g. Talon, Mortein, Ratsak Fast Action, Pestoff Rodent Bait 20R, Klerat) .

There is a poison called Cholecalciferol, which is not an anticoagulant. Found in Rampage and Solentra brands, it is said not to pass on to secondary predators. But one web site said that: “This is one of the most dangerous mouse and rat poisons on the market. Cholecalciferol, or activated vitamin D3, causes a life-threateningly high calcium and phosphorus level in the body, resulting in severe, acute kidney failure, cardiovascular abnormalities, and tissue mineralization. This can progress to life-threatening disease. Even though this is a vitamin, it is toxic to dogs, cats, and children as well as rodents”.

So unfortunately Cholecalciferol does not seem to be a solution.

NB Any poison will be a threat to children and pets.

Managing rats without poisons in Australia.

  • Non-toxic solutions for rats are clearly the bast ways to go, for example: keep your place clean and tidy,
  • secure chicken runs and compost heaps from rats;
  • learn how to use rat traps,
  • learn to live with  pythons (excellent, non-polluting rat killers!), and
  • encourage and support raptors (or birds of prey). Owls in particular often specialise in catching rats.

See more information below.

Living with pythons.

(1)  Pythons are NOT poisonous . Generally they are no more dangerous than a cat or a dog- if you tread on one or try to kill one, expect it to defend itself!

(2) Living with pythons may require overcoming a fear of snakes. It does mean knowing where your python goes at night so that you do not accidentally tread on it!

NB Some consider that being knowledgeable enough to live with pythons is the hallmark of true Australian!

Of course poisonous snakes also eat rats, but generally they avoid people as much as possible.

Rat traps.

Lethal rat traps (the old fashioned “snapper” or are modern versions) are an excellent non-toxic solution. You will have to learn the mostly-now-lost skills of how to outwit rats (which learn fast!), and then you have to deal with blood (always put newspaper under the trap) and small corpses. And you have to make sure they don’t snap on to pets or children.

“Humane” rat traps are good (they catch the rat alive), and then you face the choice of delivering the animal to a remote location, or euthanasing it or despatching it yourself.

Cats and dogs.

Cats have long been consider good natural rat catchers in Europe, Asia and North America. However they have a devastating effect on native Australian mammals and birds. At the Narara Ecovillage cats are only allowed if they are kept inside or in caged outdoor areas.

In Brisbane in the past the Council use to employ rat catchers who used fox terriers. Worth a try!

Sonic repellers.

Bunnings and some supermarkets also sell sound repellers. We cannot vouch for their safety: the packets say ” safer than rat poisons”, whatever that may mean. At least that solution recognises the the main objective is to keep rats out of houses. After all, rats will always be around somewhere.

Professional pest controllers.

If you feel the need to use a professional pest controller, choose one like Systems Pest Management that will only use poison as a last resort.

Living with Raptors (Birds of Prey)

Many raptors specials in hunting rodents. This includes many owls as well as diurnal predators. They are excellent natural rat controllers.

There is a serious danger that our children will inherit a world without owls; or, as Mike Lohr put it, we will end up with “silent nights”. Mike’s research has shown that even Boobook Owls, the commonest Australian owls, are affected by rodenticide poisons, especially if they live anywhere near human settlement.

Barn Owl photo by Ian Benson, Hunter region NSW May 2018.

The website and Facebook of RATS (Raptors Are The Solution) has excellent information and resources like the poster below.

There is still clearly a need to convince some people that raptors are a good thing- and that it is up to you to protect your chickens, and not up to raptors to avoid them!

Virtually all wildlife relies on humans being sensible; only we know the big picture of how life works on our planet.

FOR A RECENT STORY ON THIS TOPIC, SEE: http://www.abc.net.au/news/2018-07-12/something-killing-barn-owls-in-victoria/9980016.

Conclusion.

We have inherited a wonderful natural ecosystem, with eagles, hawks, owls, pythons and rats: let them get on with it, and enjoy the wonderful spectacle of Nature at work in your own back yard.

NB THE PERSONAL OPINIONS ABOVE ARE JUST THAT-PERSONAL OPINIONS. Always do your own research, or seek professional advice, before choosing your solution. 

Richard Cassels.

BOOBOOK OWL (Photo RC).

Notes.

(1) http://tasmaniantimes.com/images/uploads/Anticoagulant_pesticides_in_Australia.pd